Most often used in electrochemical research, the potentiostat is a circuit that controls the voltage between a working electrode and a reference electrode contained in an electrochemical cell. The working electrode acts as a surface for the electrochemical reaction to occur, while the reference electrode is used to measure the potential of the working electrode .
By controlling the voltage between the two electrodes, the potentiostat is able to measures the current through a reaction, which allows scientists, lab technicians and engineers to measure and analyze a wide variety of reactions, including environmental monitoring, health monitoring, and food monitoring. This versatility makes the potentiostat an extremely useful multi-purpose tool with tremendous implications for everyday use from allowing patients to perform at home blood tests and run routine health diagnostics, to letting dieters and nutritionists test the chemical composition of foods, and even measuring environmental contamination in lakes, wells, and the water that come straight from the tap . Just imagine the possibilities if every home were equipped with a potentiostat!
However, the potentiostat is costly, with expenses ranging from $1,000 for a basic set up, to $10,000 for research grade model . At 50 cm by 20 cm and weighing in at 5 kilograms (11 lbs) or more, it’s an unwieldy piece of equipment to both use and store around the house. The clunky size and the lack of wireless connectivity prohibits the potentiostat from being a mobile device. This coupled with the high price has severely limited the potentiostat’s potential for use by the general public and has, unfortunately, kept many who would benefit from the technology ignorant of its many uses.
Enter the Cheapstat – a sized-down, cost efficient potentiostat recently developed at the University of California, Santa Barbara. With a sticker price of just under $80, the Cheapstat employs digital technology, using a custom printed circuit board, clips, and a microcontroller to shrink the potentiostat into the palm of your hand. While the Cheapstat does not match the capabilities of research-oriented potentiostats found in labs, its wide array of waveforms and usage of a modern computer interface puts it far beyond previous iterations of miniature potentiostats in both capability and usability.
The three clips mirror the three electrodes, acting as the measuring/input device of the Cheapstat, while the microcontroller acts as the control module, analyzing and receiving data through the printed circuit board. When the measurements are complete, data can be exported to a computer via micro-USB cable to generate visualizations in the form of graphs and charts . However, this process is currently being made even simpler with current research and development focused on integrating the potentiostat with Bluetooth technology. Using Bluetooth, data can be sent to a smartphone and analyzed in real time. This ability to track and report changes instantaneously, which leads to both faster diagnosis and response times, coupled with increased portability, maximizes the Cheapstat’s potential uses. Particularly in the developing world where relatively inexpensive and accessible real-time data analysis could have monumental effects in quality of health care, and the assessment and monitoring of environmental issues like clean drinking water . Even in a common household, Cheapstat can be used to check biosensors in the blood, detect DNA, monitor environmental contaminants, and even check how much power is left in batteries.
Cheaper, smaller, and easier to use than ever, the Cheapstat provides an exciting look into how technology can give the everyday person increased autonomy in caring for themselves and their families. The technology is open source, and can be found on the official Cheapstat website. If you don’t want to build it yourself, there are plenty of online stores which sell completed Cheapstats. Whether you want to build it or buy it, the Cheapstat is always just one quick Google search away.
- “Potentiostat Fundamentals.” Gamry Electronics. March 20, 1996. Accessed May 7, 2016. http://www.gamry.com/application-notes/instrumentation/potentiostat-fundamentals/.
- Rowe, Aaron A., Andrew J. Bonham, Ryan J. White, Michael P. Zimmer, Ramsin J. Yadgar, Tony M. Hobza, Jim W. Honea, Llan Ben-Yaacov, and Kevein W. Plaxco. PLOS One, September 13, 2011. http://dx.doi.org/10.1371/journal.pone.0023783.
- “CheapStat Open Source DIY Potentiostat.” Dangerous Prototypes. September 27, 2011. Accessed May 7, 2016. http://dangerousprototypes.com/blog/2011/09/27/cheapstat-open-source-diy-potentiostat/.
Mihir Pandya is a rising senior at Lynbrook High School and thoroughly enjoys researching in STEM related fields. He is an aspiring engineer and researcher. Mihir is not receiving any money or royalties from Cheapstat sales.